This invention relates generally to the ice making art, and more particularly, to a method and apparatus utilizing atmospheric conditions to make ice.
In the prior art, the conventional way of making ice is to use a brine tank and circulate a refrigerant through coils submerged in the brine. Containers known as ice cans are filled with water and then lowered into the brine until frozen. These containers are rectangular in shape and tapered inwardly from top to bottom to permit easy removal of the ice from the can and to prevent rupture of the can when the water freezes. These cans are filled with approximately 315 pounds of water to a level of about three or four inches from the top to prevent spilling of the water and to prevent the brine water from spilling into the cans when the cans are lowered into the brine tank. An air hose is submerged about one half of the depth of the water in the ice can to agitate it to cause it to freeze faster. The water freezes from the bottom up and from the outer sides of the can toward the center. When it is about two thirds frozen, the air hose is removed and the rest of the water is permitted to freeze.
It is also known that water does not freeze when it is cooled down to 32.degree.F, but rather an additional amount of heat must be removed before there is a change of state. Specifically, 144 BTU's (British thermal units) per pound must be removed before there is a change of state from liquid to solid. The same amount of heat, 144 BTU's, must be added to change ice to water without changing the temperature. Therefore, for every pound of ice at 32.degree.F there are 144 BTU's cooling effect. If ice could be used in, for example, chilled water systems, this cooling effect from the ice would be an available energy source, over and above that cooling effect which is normally available in the usual cooling system which requires a separate energy source to reduce the temperature of the cooling media. Not only would the 144 BTU's per pound be recovered as the ice melts into water, but also the water so produced would be at 32.degree.F and would provide an additional cooling effect by virtue of the differential in temperature between it and the discharge water in the cooling system.
Electric generating power houses use thousands of tons of water daily in the condensers for converting steam back to water in order to pump the demineralized water back into the boiler. The cooling water returns to a stream or river after it has passed through the condenser at much higher temperatures than the river water, creating thermal pollution and often killing marine life. Some power houses also use huge cooling towers which stand several hundred feet into the air, creating a natural draft to cool the condenser water to a temperature low enough to be legally returned to the stream or river, and in some cases recycled through the condenser. These huge cooling towers admit a great amount of heat and tons of vapor causing thermal pollution of the air and loss of the much needed water at a time of the year when water is most needed; and the thermal pollution adds to the heat and humidity at a time of year it is least needed. During the hot summer months there will be little cooling effect of cooling water when it reaches the power house due to the amount of heat the water was exposed to in atmospheric conditions. Such water is typically taken from rivers and streams which are at their lowest during the summer months. This water is also returned to the streams and rivers. Thus the cooling effect for each pound of water will be minimal.
In most all sections of the world today there is an energy shortage, and in many sections there are water shortages in the summer months with high thermal pollution of the air and rivers.